Many devices and systems (such as smartphones, tablets, digital cameras, security systems, computers, and so on) include cameras for various applications. Each camera requires a minimum brightness or luminance in a scene in order to capture the scene. For example, a camera might not accurately capture colors and details of a scene with low light settings (such as indoors, at night, and so on). To compensate for low ambient light, cameras use a flash in order to increase the brightness of the scene.
Many devices use a xenon flash tube or a light emitting diode (LED) for flash photography. Each flash tube or LED is typically associated with a color temperature, and the flash tube or LED light at the color temperature may cause a color cast or other undesirable color characteristics in an image. Although an undesirable color cast may be removed by post-processing the image, image post-processing may cause areas of an image with greater ambient light to have a warm color cast or other undesirable color characteristics.
To prevent undesirable color characteristics in captured images, some devices include two or more light sources (such as multiple flash tubes or multiple LEDs) with different color temperatures to adjust the total color temperature for a flash, for example, to reduce mismatches between the flash color and the scene's illuminant color. However, because flash tubes or LEDs of a same type may have minor variations in color temperature, flash systems with multiple flash tubes or LEDs typically require calibration. LEDs require during manufacture, for example, to compensate for variations in color temperature between the LEDs.